<div class="js_dialog" id="mobileAlert" style="opacity: 1;display:none">
    <div class="mask"></div>
    <div class="weui-dialog">
        <div class="weui-dialog__bd"></div>
        <div class="weui-dialog__ft">
            <a href="javascript:;" onclick="hiddenDiv('mobileAlert')" class="weui-dialog__btn weui-dialog__btn_primary">知道了</a>
        </div>
    </div>
</div>